Dingwall Castle is believed to have been established by Norse settlers in the area in the 11th century. During the Wars of Scottish Independence the castle was garrisoned by the forces of king Edward I of England. However it was later captured by Scottish forces for king Robert I of Scotland (Robert the Bruce) led by Uilleam II, Earl of Ross.
From the castle, the Earl of Ross (chief of Clan Ross) led the men of Ross to fight against the English at the Battle of Bannockburn in 1314. As a reward in 1321 King Robert granted Dingwall Castle with the town and lands of Dingwall to the Earl of Ross.
In 1370 a feud arose between William de Moravia, 5th Earl of Sutherland (chief of Clan Sutherland) and Aodh Mackay (chief of Clan Mackay). A meeting was arranged for them to meet at Dingwall Castle to resolve their issues. However Aodh Mackay and his son Donald Mackay were both murdered in the castle while they were asleep by Nicholas Sutherland, brother of the Earl of Sutherland.
In 1411 Domhnall of Islay, Lord of the Isles (chief of Clan Donald) captured Dingwall Castle as part of his attempt to seize the title of the Earldom of Ross. This took place shortly before the Battle of Harlaw. In 1438 the next successive Clan Donald chief, Alexander of Islay, Earl of Ross was officially recognised as the Earl of Ross and took up his residence at Dingwall Castle. His son, John of Islay, Earl of Ross was not as successful; the Earldom of Ross was confiscated from him and the castle became a royal possession once more in 1475. John Munro, 11th Baron of Foulis was then made governor of the castle, who in turn was succeeded by Andrew Munro, 2nd of Milntown. The next governor in 1488 was Sir James Dunbar.
In 1507 Andrew Stewart, Bishop of Caithness carried out improvements after the castle had been assaulted by the MacDonalds and Mackenzies. The Crown abandoned Dingwall Castle in about 1600 and it eventually fell into a ruin. The castle ceased to be maintained after the death of king James VI of Scotland in 1625. It was used as a quarry until 1817 when it was finally levelled and only a few fragments remain.
A tunnel still exists that runs from the site of Dingwall Castle to the basement of nearby Tulloch Castle. The tunnel has now collapsed, but it is possible to view this passageway through an air vent on the front lawn of Tulloch Castle's grounds.
References:Sigmaringen Castle was first mentioned in the year 1077 in the chronicles of Petershausen monastery. The oldest parts of the castle are concealed beneath the alterations made during the 17th and the 19th centuries. The secret of the earliest settlement built on this defendable rock will never be fully revealed: large-scale excavation work would be necessary, which the extensive land development renders impossible. Judging from the many Roman remains unearthed in the area around Sigmaringen, the 12th century keep known as the 'Roman Tower' could be traced back to a Roman predecessor.
The castle remains that have been preserved (gate, great hall and keep) date back to the Staufer period around 1200. The castle remains were integrated into subsequent buildings. The foundations of the castle buildings are to a large extent identical to the surrounding castle wall.
These remains give us a good idea of how the castle might have looked during the 12th century.